Sandbox



FIG. 1 is a perspective view of the sandbox;

FIG. 2 is a rear view of the sandbox;

FIG. 3 is a left view of the sandbox;

FIG. 4 is a right view of the sandbox; and,

FIG. 5 is a top plan view of the sandbox.

The broken lines are directed to environment and are for illustrative purposes only, the broken lines form no part of the claimed design. 

The ornamental design for a sandbox, as shown and described. 